The only way to be sure that what you are buying is “official” is to purchase your tickets from a company that has agents that will purchase in the real world the Powerball tickets online that you have selected. If you are a more trustworthy person and don’t need a scanned copy of your Powerball tickets online then by all means go for an online lottery ticket provider that follows the insurance model. 
Playing with theLotter is easy and secure. A confirmation email at time of ticket purchase is sent to you as proof of ownership. Furthermore, you will receive a scanned copy of the ticket in your account as proof-of-purchase after the ticket has been purchased by our local office. All winnings are 100% yours -- theLotter has no legal claim to your tickets per the Terms of Use. Since 2002, theLotter has paid out well over $90 million in prize money to more than 4 million winners!
Unclaimed prizes are kept by the lottery jurisdiction. If a Grand Prize goes unclaimed, the money must be returned to all lotteries in proportion to their sales for the draw run. The lotteries then distribute the money, based on their own jurisdiction's laws, to other lottery games or to their jurisdiction's general fund, or otherwise as required by law.
Powerball pays out the largest lottery jackpots in the world. Simple as. The biggest of the bunch arrived in Jan 2016, when three ticket-holders shared a prize fund worth $ 1.58 Billion. For your chance to win a world-beating lotto prize, pick 5 from 69 plus the Powerball and bet on one of our Thursday or Sunday night draws. Highest ever jackpot: $ 1.586 Billion

Remember, the advertised Mega Millions jackpot is the annuity jackpot, which means it's the amount that you would receive if you were to opt for the money to be paid out over 29 annual payments (plus a one-off initial payment). For example, for an advertised jackpot of $200 million, the initial payment would be approximately $3 million, with future payments growing to as much as $12.4 million per annum. However, almost all jackpot winners take the cash option that is paid in one lump sum that, on average, is 60% of the advertised jackpot.
Powerball offers an optional multiplier known as the Power Play, which multiplies the seven bottom prize divisions by 2, 3, 4, 5 or 10 times, depending on the draw and jackpot size. Matching five main numbers and the Power Play still makes you a multi-millionaire by doubling Powerball’s second place prize to a staggering $2,000,000! To add the multiplier, simply check the Power Play box when you buy your Powerball tickets online.

MUSL and its members accept all investment risk and are contractually obligated and liable to the winner to make all scheduled payments to annuity winners. If a jackpot ticket is not claimed, the funds in the prize pool are returned to members in proportion to the amount they contributed to the prize pool. The members have different rules regulating how unclaimed funds are used.[2]

The structure of the draw is one which regular lottery players will be very familiar with; players must pick 5 regular numbers from a pool with a total of 69 numbers and in addition to these regular number picks, you also choose one bonus ball (known as the Powerball) from a pool of 26. These two pools of numbers are mutually exclusive and remain completely separate throughout the drawing procedure. In order to jackpot the US Powerball, you need to match all 5 regular numbers and the Powerball. Do this and you are instant Powerball millionaire – it’s as simple as that!
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